The Omni-Directional Thickness (ODT) tool is used to measure the average casing wall thickness and detect variations due to physical deformation or corrosion to the inside or outside of the pipe. It measures the phase shift of an induced magnetic field in the pipe that surrounds the tool over a 1-ft vertical interval. The phase shift is affected by the magnetic properties of the casing material and is directly proportional to the thickness of the casing.

The tool runs simultaneously with the GR Energy Services Multifinger Caliper tools, allowing real-time measurement of the pipe internal diameter and average thickness. The tool also incorporates an internal temperature probe. The ODT tool can also be run alone in analog mode.

The ODT outputs one raw thickness signal, which is proportional to the average thickness of the surrounding pipe. The tool measures this signal, disregarding the horizontal distribution of the thickness. This means that in the presence of local anomalies, the ODT tool does not differentiate local damage from overall corrosion.